In a conventional process for making transportation fuel, Fischer-Tropsch derived wax is cracked to make diesel fuel. However, the Fischer-Tropsch process also produces condensate, which is predominantly a combination of alkanes, olefins, and alcohols in the C3-C18 range. The C9+ condensate fraction can be blended into diesel, optionally after hydrotreating; but the C8 and lighter (C8−) fraction comprises a naphtha range blend that typically has less value than the distillate range products. Also, the cracking of Fischer-Tropsch wax to make diesel fuel is accompanied by the formation of relatively low value hydrocrackate naphtha.
There is a need for processes for upgrading Fischer-Tropsch derived hydrocarbon fractions, including Fischer-Tropsch light condensate and Fischer-Tropsch derived hydrocrackate naphtha, while maximizing the yield of distillate.